Google ADK Crash Course
A comprehensive tutorial series for learning Google’s Agent Development Kit (ADK) from zero to hero. Build flexible, model-agnostic AI agents with Google’s powerful framework, from simple text processing to advanced multi-agent orchestration patterns.Updated for Gemini 3 Flash: All tutorials use the new Gemini 3 Flash model (
gemini-3-flash-preview)What is Google ADK?
Google ADK (Agent Development Kit) is a flexible and modular framework for developing and deploying AI agents. It’s optimized for Gemini but is model-agnostic and deployment-agnostic, making it compatible with other frameworks.Flexible Orchestration
Define workflows using workflow agents or LLM-driven dynamic routing for sophisticated control.
Multi-Agent Architecture
Build modular applications with multiple specialized agents that collaborate seamlessly.
Rich Tool Ecosystem
Use pre-built tools, create custom functions, or integrate 3rd-party libraries like LangChain.
Model-Agnostic Design
Work with Gemini, OpenAI, Claude, or any other model provider.
Deployment Ready
Containerize and deploy agents anywhere with deployment-agnostic architecture.
Built-in Evaluation
Assess agent performance systematically with integrated evaluation tools.
Plugin System
Handle cross-cutting concerns like logging, monitoring, and error handling.
Safety & Security
Built-in patterns for trustworthy agents with callback monitoring.
Complete Learning Path
This crash course covers 9 comprehensive tutorials:🌱 Foundation
🔄 Model Flexibility
📊 Structured Data
🔧 Tool Integration
Tutorial 4: Tool-Using Agents
Four Types of Tools - Comprehensive tool integrationADK supports multiple tool types for maximum flexibility:1. Built-in Tools (Gemini models only):2. Function Tools:3. Third-party Tools (LangChain, CrewAI):4. MCP Tools (Model Context Protocol):What you’ll build:
- Web search agents with Google Search
- Code execution agents
- Custom function integrations
- LangChain tool wrappers
- MCP server connections
💾 Memory & State
🔔 Monitoring & Control
Tutorial 6: Callbacks
Lifecycle Monitoring - Track agent behaviorThree types of callbacks for complete visibility:1. Agent Lifecycle Callbacks:2. LLM Interaction Callbacks:3. Tool Execution Callbacks:What you’ll build:
- Agent performance monitors
- LLM usage trackers
- Tool execution loggers
Tutorial 7: Plugins
Cross-Cutting Concerns - Global agent behaviorPlugins handle concerns across all agents:Plugin capabilities:
- Global callback management
- Request/response modification
- Error handling and logging
- Usage analytics and monitoring
🤝 Multi-Agent Systems
Tutorial 8: Simple Multi-Agent
Multi-Agent Researcher - Coordinated specialist agentsBuild a research pipeline with multiple specialized agents:Workflow: Research → Summarize → Critique → ReportWhat you’ll build: Comprehensive research system with specialist agents
Tutorial 9: Multi-Agent Patterns
Advanced Orchestration - Three workflow patterns1. Sequential Agent - Deterministic pipeline:Use case: Business implementation plans with market research, SWOT analysis, strategy development, and implementation planning2. Loop Agent - Iterative refinement:Use case: Iterative content refinement until quality threshold met3. Parallel Agent - Concurrent execution:Use case: Simultaneous competitor analysis across multiple dimensionsWhat you’ll build:
- Sequential business planning pipeline
- Iterative content crafting loop
- Parallel competitive analysis
Quick Start
Tutorial Structure
Each tutorial follows a consistent structure:README.md
README.md
Concept explanations, learning objectives, and detailed documentation
agent.py
agent.py
Agent implementation with clear, commented code
app.py
app.py
Streamlit web interface for interactive testing (when applicable)
requirements.txt
requirements.txt
Python dependencies for the tutorial
Key Features & Capabilities
Model Providers Supported
- Google Gemini
- OpenAI
- Anthropic Claude
Tool Integration Examples
Workflow Agent Patterns
Sequential
Deterministic PipelineExecute sub-agents in order, each building on previous results.Best for: Step-by-step processes, analysis pipelines
Loop
Iterative RefinementRepeat sub-agent execution until condition met or max iterations reached.Best for: Quality improvement, content refinement
Parallel
Concurrent ExecutionRun multiple sub-agents simultaneously and merge results.Best for: Independent analyses, multi-dimensional evaluation
Real-World Applications
Research Systems
Multi-agent research pipelines with web search, summarization, and critique
Business Planning
Sequential analysis from market research through implementation planning
Content Creation
Iterative refinement loops for high-quality content generation
Data Extraction
Structured data extraction with Pydantic validation
Competitive Analysis
Parallel evaluation across multiple dimensions and competitors
Model Comparison
Test and compare different AI models for your use case
ADK Advantages
Model-Agnostic
Model-Agnostic
Use any model provider (Gemini, OpenAI, Claude) without changing code. Switch models based on cost, performance, or capabilities.
Deployment-Agnostic
Deployment-Agnostic
Deploy anywhere - containers, serverless, on-premise. No vendor lock-in.
Rich Tool Ecosystem
Rich Tool Ecosystem
Built-in tools, custom functions, LangChain integration, CrewAI tools, and MCP support.
Flexible Orchestration
Flexible Orchestration
Sequential, loop, and parallel workflow patterns out of the box.
Production Ready
Production Ready
Callbacks, plugins, error handling, and monitoring built-in.
Prerequisites
Optional: Understanding of async patterns, Pydantic basics, API concepts
Environment Setup
Create a.env file in your project:
.env
Learning Tips
Common Issues & Solutions
API Key Issues
API Key Issues
- Ensure
GOOGLE_API_KEYis set in.envfile - Verify key is valid from Google AI Studio
- Check key has necessary permissions
Import Errors
Import Errors
- Install ADK:
pip install google-adk - Verify Python 3.11+
- Check requirements.txt dependencies installed
Model Compatibility
Model Compatibility
- Built-in tools (GoogleSearchTool) only work with Gemini models
- Use function tools for model-agnostic implementations
- Check model name spelling and availability
Progress Tracker
- Tutorial 1: First ADK agent
- Tutorial 2: Model-agnostic agents
- Tutorial 3: Structured outputs
- Tutorial 4: Tool integration (all 4 types)
- Tutorial 5: Memory and sessions
- Tutorial 6: Callbacks for monitoring
- Tutorial 7: Plugins for cross-cutting concerns
- Tutorial 8: Simple multi-agent researcher
- Tutorial 9: Advanced workflow patterns 🎯
Additional Resources
ADK Documentation
Official Google ADK documentation and guides
Google AI Studio
Get API keys and test models
Gemini API Reference
Detailed Gemini API documentation
Pydantic Documentation
Learn about data validation
Next Steps
Start Learning
Set up your environment and begin with Tutorial 1: Your First ADK Agent
